Synergistic insecticidal compositions



United States Patent 1958, Ser. No. 767,256

Claims. (Cl. 167-30) vThis invention relates broadly to insecticidal compositions, and more particularly to insecticidal compositions containing an organic carbamateacid derivative and 0,0- dimethyl O-(2-chloro-4-nitrophenyl) thiophosphate, hereina'fter referred to as 04124. More particularly, this invention relates to synergistic insecticidal compositions of these compounds wherein the insecticidal effectiveness of each component'is enhanced by the presence of the other to produce an unexpectedcombined effect.

When two or more substances in combination show an unexpectedly high activity, as, for instance, insecticidal activity, the resulting phenomenonis called synergism. The mechanism of synergism is by no means understood. It is, in fact, quite probable that it differs with different synergistic combinations. 1 The term synergism can be defined, however, as a cooperative action which is encountered in combinations of two or more biologically active components in which the combined activity of the two components exceeds the sum of the activities of the components when used alone. of the mixed components cannot be predicted from known values of the individual components, but is unpredictable }and depends on the individual activity of neither.

It is an object of this invention to provide insecticidal compositions of enhanced killing power. Another object of this invention is to produce novel compositions ,containing compounds capable of synergizing the knockdown and killing properties of individual toxicants. A further object of this invention is to provide compositions including a relatively toxic phosphorus containing insecticide in which superior insecticidal activity is obtined because of the synergistic effects, but in which the ultimate toxicity to warm-blooded animals is greatly reduced because of the lower concentrations of the phosphorous compounds required when used in combinations with the relatively less toxic carbamates. Other objects and advantages of the invention will become apparent from the description of the invention set forth below.

According to this invention, there are provided synergistic insecticidal compositions comprising 0,0-dimethyl O-(2-chloro-4-nitrophenyl) thiophosphate, hereinafter called C-4124, and a carbamate ester of the general formula:

The insecticidal activity fications from the method Patented Aug. 8, 1961 2. wherein R is selected from the group consisting of furfuryl, isopropyl and tert-butyl radicals. These cat-bamates may be prepared as described in copending application Serial No. 812,113, filed May 11, 1959.

The synergistic insecticidal compositions of this invention may be used on a wide variety of insect and mite species, but are particularly effective against houseflies. The combinations are highly effective and economical to use for such large-scale insecticidal requirements as the control of truck crop, forage crop and orchard insects.

The synergistic compositions of this invention can be formulated as aqueous emulsions, as dry or wettable powders, as solutions or in any other suitable vehicle. The insecticidal compositions can be utilized as sprays, as dusts, as aerosol mixtures, insecticidal coating compositions, and as residues. In general, they can be applied by methods commonly used for control or eradication of insects, mites and the like. Thus these insecticidal compositions can be formulated with solvents, diluents and carrier media, adhesives, spreading, wetting and emulsifying agents and other ingredients.

The relative proportions of the active ingredients as well as inert carriers, solvents, dispersants and the like may vary within wide limits. A

Thus the relative proportion (ratio) of the C-4124 to the carbamate ester can range from 20 parts of the former per 1 part of the latter to 1 part of the former per 40 parts of the latter and preferably about 1 part of the former to 5 parts of the latter.

The quantities of the component toxicantsin the final insecticidal compositions can range from 0.01% to 25.00% for the C-4124 and from 0.05% to 50.00% for the carbamate, and preferably from 0.10% to 10.00% for the C-4124 and from 0.10 to 25.00% for the carbamate.

The test method employed was the turntable method which is described in the article by Campbell and Sullivan, Soap and Sanitary Chemicals, 14 (6), 119-125, 149 (1938). The tests were carried out with slight modidescribed in the reference above.

The table used is equipped with eight towers. -The period between spraying and actual exposure of settling mist to the test flies is 6 seconds, and flies are exposed to the settling mist for 10 minutes. The sprayer is operated at 5 p.s.i.g. Five milliliters of test solution are used for eachtest. There is a filter paper placed in the bottom of each test dish containing the houseflies undergoing tests. Mortality counts are made after 24 hours.

wherein R is selected from the group consisting of fur- 4o furyl, isopropyl and tert-butyl radicals, said ingredients being present in a ratio of about 1 part of said thiophosphate to about 5 parts of said carbamate.

2. A synergistic insecticidal composition comprising 0,0-dimethyl -(2-chloro-4-nitrophenyl) thiophosphate 45 and phenyl N-furfuryl carbamate, said ingredients being present in the ratio of about 1 part of said thiophosphate to about 5 parts of said earbamate ester.

3. A synergistic insecticidal composition comprising 0,0-dimethyl 0-(2-ch1oro-4-nitr'ophenyl) thiophosphatev and phenyl N-isopropylcarbamate, said ingredients being present in the ratio of about 1 part of said thiophosphate to about 5 parts of said carbamate ester.

4. Synergistic insecticidal compositions comprising 0,0-dimethyl 0-(2-chloro-4-nitrophenyl) thiophosphate 'andphenyl N-tert-bntyl te, said ingredientsbe- In the table which follows,.the quantities are expressed ing present in the ratio of about 1 part .0! said thiophosby weight unless otherwise indicated: phate to about 5 parts of said earbamste ester. Table 1' i Carbonate amu e I Mortality Oonosn- Oonosn- TsstMethod Tsst'fluhjset stfllHours B tfation Name tzation 7 (percent) 103 51.) 10o l'uriuryl. 1500 0-412 20 Turntable.-. Housgflies-.. 5: Do 10o 0-4124 20 m m 7 s4 Isopmpy 500 In En la 0-4124 20 m m as Do 10o 0-4124 20 m m 81 TBWBDWI 500 on rn 4 0412 20 in in M Do... 04m 20 m s2 5. The method of killing insects which comprises applying to the insects and their habitat a synergistic insecticidal composition comprising 0,0-dimethyl O-(2- ehloro-4-nitrophenyl)thi pphosphate and a carbamate ester of the general formula:

. I I I wherein R is selected-from the group consisting of furfuryl, isopropyl and tert-butyl radicals, said ingredients phosphate to about 5 parts-of said carbamate.

References Cited in the file of this patent UNITED STATES PATENTS Jelinek Apr. 11, 1950 Gysin May 25,1954

OTHER REFERENCES King: US. Dept. Agr. HandboohNo. 69, May 1954, pp. -108. a a

Chemical Age, vol; 63, No. 1631 (1950), p. 540.

1 3. Rgarfi-k: US. Dept. Agr. Bulletin, 15-344 (May 1935),

PP. 7 Q

Frear: Chemistry of the Pesticides, 3rd Ed-., January 1955, pp. 73-91.

Horsfall: Fungicides and Their Action, vol. H, 1945,

being present in a ratio of about 1 part of said thio- Sharp: Agr. News Letter, January-February 1952, pp. 

5. THE METHOD OF KILLING INSECTS WHICH COMPRISES APPLYING TO THE INSECTS AND THEIR HABITAT A SYNERGISTIC INSECTICIDAL COMPOSITION COMPRISING O,O-DIMETHYL O-(2CHLORO-4-NITROPHENYL)-THIOPHOSPHATE AND A CARBAMATE ESTER OF THE GENERAL FORMULA: 